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The first commercial licensing of CP/M took place in 1975 with contracts between Digital Systems and Omron of America for use in their intelligent terminal, and with Lawrence Livermore Laboratories where CP/M was used to monitor programs in the Octopus network. Little attention was paid to CP/M for about a year. In my spare time, I worked to improve overall facilities... By this time, CP/M had been adapted for four different controllers....
In 1976, Glenn Ewing approached me with a problem: Imsai, Incorporated, for whom Glenn consulted, had shipped a large number of disk subsystems with a promise that an operating system would follow. I was somewhat reluctant to adapt CP/M to yet another controller, and thus the notion of a separated Basic I/O System (BIOS) evolved. In principle, the hardware dependent portions of CP/M were concentrated in the BIOS, thus allowing Glenn, or anyone else, to adapt CP/M to the Imsai equipment. Imsai was subsequently licensed to distribute CP/M version 1.3 which eventually evolved into an operating system called IMDOS

Ask Bill [Gates] why the string in [MS-DOS] function 9 is terminated by a dollar sign. Ask him, because he can't answer. Only I know that.

Quoted in James Wallace and Jim Erickson (1991-05-08), "Bill Gates: Of Mind and Money", Seattle Post-Intelligencer

I expected too much of educators. I expected them to understand, in a sense, the sugar-coated concepts of LISP used in AI that were embodied in the Logo language. It was then that I learned that computers were built to make money, not minds.

Unpublished memoir Computer Connections, on the prevalence of BASIC in programming education; quoted in a eulogy delivered by Tom Rolander

He is divisive. He is manipulative. He is a user. He has taken much from me and the industry.

It's fun to sit at a terminal and let the code flow. It sounds strange, but it just comes out my brain; once I'm started, I don't have to think about it.

You need to study other people's work. Their approaches to problem solving and the tools they use give you a fresh way to look at your own work.

The ALGOL compiler was probably one of the nicest pieces of code to come out at that time. I spent hours trying to fix and change the compiler. Working with it so closely affected the way I think about programming and had a profound influence on my style.

Gary Kildall was one of the original pioneers of the PC revolution. He was a very creative computer scientist who did excellent work. Although we were competitors, I always had tremendous respect for his contributions to the PC industry. His untimely death was very unfortunate and he and his work will be missed.

It was Gary's bad luck that put him up against the most skilled businessman of all time. Anyone looks like a failure standing next to Bill Gates.

Alan Cooper, quoted in Freiberger and Swaine (1999), Fire in the Valley

I've told this story to lots of people and they just won't get it. All they want to get is that IBM showed up and Gary was off flying his aeroplane. The problem is that this is very wrong.… The real issue wasn't that Gary refused to talk to IBM. The real issue was that Microsoft had a much better vision for the business. Gary was very laid-back. He did not care that much.

Gordon Eubanks, "Recollections of Gary Kildall", on IBM's attempt to license CP/M for the IBM PC

When we failed to produce an operating system in a timely manner, Glenn started talking with Gary about CPM, which Gary had written for Intel under contract. It took several months of twisting Gary's arm to get Gary to port it to the 8080. The final success came when Glenn talked Gary into just separating the I/O from the rest of it, with Glenn promising to re-write the I/O module for the IMSAI 8080 (which he did). So CPM on the IMSAI was a joint effort between Glenn and Gary.

"Intel had hired him a few months earlier to write a control program monitor to run on their little demo system for 8008 and now 8080.... Glenn knew this and he would be talking with Gary, and he started twisting Gary's arm. He said, "Hey Gary, why can't we run this in this IMSAI?" "The I/O's all different, won't run."
But Glenn persists and finally makes a deal with Gary. He says, "Okay Gary, if you split out the I/O, I'll write the BIOS, basic I/O's system," and Glenn named it then. "We'll split it out separately. I'll write that part, as long as you can make a division in the program there."
And he got Gary to do that and Glenn put those two pieces together and was running Gary's CP/M on an IMSAI. Glenn let us know that, and it wasn't too much later than Bill was down there making arrangements with Gary Kildall to license CP/M....
Now that the BIOS is separated out, anybody could write a BIOS for their machine, if it was 8080-based, and run this, so he started selling that separately under the company Digital Research that he formed and did quite well."